The Portable Freeware Collection Forums

Problems like this are almost never resolved, unless the author has a solution.

As you can see, the error message is about something being write-protected.
I copied this app to a flash drive. Absolutely nothing is write-protected, so I
cannot use this app.

Does anyone know why I'm receiving this error message?

I guess you're talking about this program? http://www.softpedia.com/get/System/OS- ... nger.shtml

There's a variety of reasons why tools can be set to read-only. Have you tried it on more than one system? Also, since this is changing extensions, it might be something that needs to be run in admin.